Ramadan is not only the month of Fasting, but it is the chance to get more near to Allah. In this month, reward for good actions becomes more than 70 times, so all Muslims try to get more & more reward by Fasting, Praying, Reading Quran etc

Rules Related to Fasting

The obligation of fasting
a) The time for fasting is from the rising of the second dawn until the setting of the sun.
b) Fasting is: abstention from eating, drinking and sexual intercourse by day with the intention.
The fasting is valid with an intention from the night, but if one did not intend until the morning, the intention suffices him between [dawn] and {the middle of the day}.

1. Things which invalidates fasting and requires full recompense.if someone intentionally does one of the following without any valid excuse(see 6 below)
a) Does not fast at all
b) Breaks fast by eating, drinking and sexual activities
c) Assuming that cupping has broken ones fast thus quit fasting for the day.

2. Expiation for the above is to
a) Fast unceasingly for two months (60 days), if one breaks fats during this one has to start anew.
b) If unable to do so, it is to feed 60 needy persons two full meal
c) If unable to do so, it is to free one slave.

3. Things that break fast and requires one to fast similar numbers of days in recompense
a) If something is entered into the body during the hours when one is supposed to fast, irrelevant of how it entered into the body.(see 5) 

To eat something which is not food such as stone particle or smoking   anything.
When water enters stomach while gargling                                    When one is fed by force even when one is sleeping or unconscious Inject medicine, place them on wounds which eventually gets in.
Eating by mistake thinking it is still night or iftar time is due while it is not.
Involuntary full mouth vomiting and subsequent swallowing of it or part of it.
When one is force into sexual intercourse or when one is sleeping or unconscious

b) Fasting without intention
c) Breaking (iftar) fast without the intention of doing so.
d) Lustful kissing of ones spouse
e) Emission of semen due to touching, kissing, masturbation.
f) Intentional vomiting.